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It never stops to amaze me how a, so-called, social animal can be so antisocial at the same time as being, so called, intelligent; if we're so intelligent how come we can't understand the benefit of sharing?

Hello everyone. I've got another probability puzzle that I actually did solve, but I feel like I may have taken a longer route than necessary to arrive at the solution. I'm wondering if there is a simpler, more elegant way to solve it than the "backwards" approach I took. Basically, the problem is that you have 40 cards remaining in a deck, with all four aces still in the deck. If you draw two cards, what is the probability that exactly one card will be an ace? I didn't know how to solve it directly, so I thought it would be easier to find the probability of *both* cards being an ace and the probability of *neither* card being an ace, and subtract those amounts from 1: 1 - ( (4/40) * (3/39) ) - ( (36/40) * (35/39) ) This works, and I understand why it does, but it feels like more of a brute force method. Is there a way to directly solve for the probability of only one card being an ace? Thanks!

Hi guys. I've been away for a while - busy with work and family and so on, and I also got a little weary of the political and social narrow-mindedness that comes up here sometimes. But the quest continues - I've still been prowling the internet for good papers on quantum theory and so on. A few days ago I ran across Schrodinger's original 1926 paper, where he lays out quantum theory from ground zero, rather than via given axioms like most modern treatments use. I've found the connection with optics to be a VERY helpful mental image. So, if we start from the beginning and presume that matter is a wave phenomenon, and work through the development alluded to above, we wind up with Schrodinger's equation connected very clearly to classical mechanics. I see how uncertainty arises - building a wave packet with a sharply defined position requires many frequency components, and each of those has a different momentum, so the momentum becomes more and more fuzzy as we make the position more well-defined. I'm left a little confused, though, trying to connect this to other stuff I've read. Specifically, if we have a localized wave packet, with many frequency components, doesn't that automatically mean that we have many quanta of energy? At least one for each frequency component? Is it even possible for a single quantum to have a localized position? It seems that a single quantum would have to reside in a single mode of the field, and that mode by definition is spread out over all of space. Another angle on the same quandary. Let's say we send a single quantum of an electron field through the double sit apparatus. That quantum is spread out all over the place, and strikes the detector with an intensity given by the interference bands of the apparatus. So far so good. But when we get a flash in a specific spot on the screen, that seems to imply that there's a sharply localized event, which seems that it would require many quanta, associated with different modes so that they combine to give that very localized effect. So how did we get from one quantum to many quanta? I feel like there's something I'm missing here - but I know there are people here who can set me straight. Maybe the electron field passing through the apparatus has many quanta of energy, just all in that one mode? I might should open another topic for this next question, but I'll put it here anyway and see how things go. This "optical analogy" path that I read up on the last few days makes it very clear to me why electrons bound to atoms can only have specific energy levels - that comes right out of the solution to the equation. So that degree of "quantization" is making a lot of sense to me. But I think in the modern point of view quantization goes much further - it applies everywhere rather than just in isolated situations. What sort of thought process do I use to step on to that more advanced point of view? I hope all of you guys have been doing well - sorry to have been so absent. Kip

Very detailed, very good paper. It even goes into some detail why gravity is classed as a pseudoforce, something a bit rare these days but pertinent to unification attempts, or failure, using a better word. http://www.blau.itp.unibe.ch/newlecturesGR.pdf

If you have a look at a Penrose diagram for a rotating or charged Black Hole, there are certain time-like paths ( as opposed to space-like which involves superluminal speeds ) which lead back to normal space-time OUTSIDE the BH's event horizon. Whether this 'outside' is in our universe or another, or even if this is a physical interpretation ( or not ), is anyone's guess

I can't think of an easier way. Subtracting the probability of an event not occurring from 1 is a pretty standard way of finding the probability of an event so kudos for thinking it up.

They are nearly parallel because of the distance. You get rays from all parts of the surface of the sun, which is why you can see the entire sun. Luckily, you only receive a tiny fraction of them, otherwise you would burst into flames. Complicated, I know ...

As we don't care about the colour of the first sock there is really only one event here (in a probabilistic sense). We could consider the equivalent problem. We already have one sock. There are 5 socks in a draw, one of the same colour you already have , two of some other colour and two of yet another colour. What's the probability of drawing a match for your sock? Put like this we can see there's only one event. So strictly speaking i'd say they are incorrect to describe these as independent events as there is just the one. I suspect they put it in there to help prod people away from thinking that they need to consider the probability of drawing the first sock. Or maybe just an honest mistake.

Indeed, Especially, given that, as individuals we aren't really all that good. It's only by cooperation that we achieve truly great things.

It often is; it certainly is if they got where they are by inheriting a company, or by getting away with sharp practice, or they happened to choose VHS rather than betamax, or they took over an existing company, or they were in the position of having a powerful friend block a competitor. You say "You make the company, or the employer pay more taxes...." And then you forget the important bit. Why is that? Is it that you don't want to acknowledge it? Anyway- since you won't look at the real world, I willpoint it out for you. You make them pay more tax and then you (as the state) use that money to do things like build roads (which practically no employer can afford) which allow the business to distribute the goods it makes. And you use it to build and run schools- so that the business can benefit from having a better educated , better trained workforce. And you use it to provide healthcare so that the business benefits from a healthier workforce- they work better , worry less and have better attendance. And so on. Now it's true that a big employer could, in principle, do any of those things. But big employers like that are rare. A government gets all the benefits of ensuring that nobody shirks their share and they also get economies of scale which no other mechanism would allow. So, there are lots of benefits that you simply ignored. You say "Rich people are not our enemies, they are the holders of the means of production." The two clauses are unrelated to eachother They often hold the means of production for no good reason except luck. When they club together and ensure that they get all the money and leave the rest in poverty then yes, they absolutely are the enemy. (and they have). https://www.theatlantic.com/business/archive/2015/12/hope-despair-inequality/421806/ I doubt that, but let's look at the alternative- the usual system that people consider is the "flat tax" rather than a progressive tax rate. It's not hard t show why it's bad for everyone. Imagine a group of people- it could be a country but it's easiest to show the reasoning with a small group- say a small town. They decide that they want a "thing" again, it doesn't matter what the thing is- a school, a park, a hospital, a statue to the town's founder- whatever. The distribution of salaries in most places is fairly similar. A few people earning a lot, many earning in the middle and a few earning very little. For simplicity there are 100 people in town. 3 earn a million a year, 5 earn just 10,000 and the rest earn 20,000. The cost of living is 9000 a year. So, let's see what happens with a flat tax. Clearly you can't set it higher than 1000 a year, because that would kill the poorest families. So, the tax income for the town can't exceed 100,000. Sadly, the Thing the town want costs 200,000. OK, let's consider a progressive tax of 5% The poorest families are still alive- which is a good thing. In fact, they are better off- they pay 500 rather than 1000 as they would under the flat tax system. They contribute 1500 between them. The "middle class" each pay 1000 and there are 98 of them, and that's another 98000 in the town's kitty, and the rich pay 50,000 each so that's 150,000 to add in. So the overall tax collected is 249500. Because they recognised the problem with flat tax they can buy the Thing and live happily ever after. (and, in case you are wondering, yes, sure, one of the 3 rich guys could simply have paid for the Thing, but it would have cost him 200,000 and this way he gets it for 50,000) Please do not ever try to tell us that progressive tax is a bad thing. (unless, of course, you think truth doesn't matter)

Intensity wouldn't diminish with distance otherwise.

It shouldn't be a political issue but anti-science types like your president make it one. Is that a euphemistic way of denying that raining CO2 levels due to industrialisation has caused climate change? It is certainly what Trump means by it.

Which is nice. It's one of the things you can do if you have a state that ensures either a viable pension or enforcement of rules that the people who promised to pay your pension actually do so. If you live an a less developed part of the world where the only people who will look after you in old age are your children then just having two would be almost suicidally stupid. Now the interesting point; resources are finite; if you have lost then that's because someone else has fewer. In many cases that's because you were in teh lucky position of being able to get them while "the other guy" wasn't so lucky. Once you realise that your "success" is not due to but largely to luck then you might see why some might

Sorry for the late reaction, I was a away a few days. My objection was against the the 'machine' part. I do not experience myself as a machine: I have no direct access to my machine-layer of the brain. Because of science I know I have a brain, and know basic principles of its functioning. But I do not have access to this functioning of my own brain. I cannot decide to let neuron 1,435,460,822 fire at will. I think my own experience in this is that 'I' am somewhere behind my eyes, and between the ears¹. And I know I can move as I want, but I have really no idea how I do this. Well, it is more than that: I try to show what this different definition of free will is. I try to show that it does not conflict with determinism and that it fits to my experience about what free will is. It does not fit to an ideological view of what free will is: the possibility to 'could have done otherwise under exactly the same circumstances', and that it is not caused by previous conditions. We are so to speak totally bathed in this ideological view on free will that we think we have such experience, where I am convinced that we have not. Part of this change of view is what it means to have been able to do otherwise, therefore was my vegetarian restaurant example. In the vegetarian restaurant I could not have done otherwise, i.e. I could not choose for a beef burger. In a 'mixed' restaurant I could have chosen the beef burger. But I took the tofu-dish. But I could have chosen otherwise. This is a relevant meaning of 'could have done otherwise' that is still relevant in a determined universe. It means the choice depends on me. But 'me' is not a homunculus in the brain. It is me as a whole. Does that help in understanding my previous reaction to you? ¹ A small funny anecdote: for about a year the company where I work replaced the telephone system with Skype. We could choose what kind of end-device we would use: an IP-telephone connected to the PC, or different kind of headsets. I chose a headset (so I can use the phone handsfree), but only with one earphone in it. I didn't want to hear the voice of some colleagues as if they would come from the middle of my head. It would place them in my head, where normally only my thoughts reside... Greetings from the Borg. What you describe is fatalism, not determinism. Fatalism does not follow from determinism. Fatalism means that what will happen is fixed, and nothing you can do will change it. But that is simply not true: what you do matters even if determinism is true. It will make the future different from what it would have been if you did something else. And what you will do depends on you inner mental activities, even if these are determined. So mathematics is also not able to produce life, don't you think? Aren't we, and all other organisms alive?

You are posting your own feelings about what you choose to accept. Trump has denied that human caused climate change and his spokes people refuse to clarify. His pivot is to discuss the economy. https://www.youtube.com/watch?v=uGEzFbRl-g8 At the one minute mark O'Reilly asks Trump specifically if he believes if humans impact climate. https://www.youtube.com/watch?v=7uJCrYuZ7yI The WH's Press Sec won't say whether or not Trump believes human impact climate. So you are basically saying that is order to find middle ground I must accept your denials and deflections? Trump has denied climate and has denied Russia hacking in his own words many times. I could spend the day copying you links. Your refusal to acknowledge what is so plainly and painfully true is a major barrier to middle ground.

One thing only saddens me. That you seem not to be genuinely seeking discussion and resolution of your point, rather you seek to provoke reaction so that you can ridicule others with more knowledge than yours, whilst at the same time sidestepping from your earlier statements. I made my last post for very good reasons, which anyone claiming to work on logic problems would normally ask "That's an interesting comment why did you say that?" In particular I stripped out simultaneity from the ladder paradox so that it would not obscure the Physics. Further I deliberately introduced a situation where no ladder of any length in any frame could in your words "pass the garage". I have pointed you at the correct resolution of the paradox which basically relies on an incomplete analysis of the situation, but without stating how explicitly. I take it that you are not actually interested in this.

Which ley-lines are you looking for? Wiki gives this map https://en.wikipedia.org/wiki/Ley_line#/media/File:Pizzalines8.png

You've found the solution to a slightly more difficult problem: the probability of a particular colour match. But here we don't care about the particular colour, only that they match. It is a bit odd for it to mention 'uniformly' but you seem to have understood it correctly: all it means is that each sock has an equal chance to be chosen. I would have assumed that anyway - but maybe someone objected that they were different sized socks or something. I agree that choosing the second sock would be a dependent event for the problem you have answered. I think it is a subtle clue to the question you should be answering.

Because I can. Whataboutism in whatever trolly format shouldn't stand, no less an OP on a science forum with rules governing that sort of thing.

Yup!

The 'laws of Physics' ALWAYS apply. It is our modeling that ceases to apply in some conditions.

A GW wave is a superposition of 10 waves, the only two waves are the Tranverse and traceless wave components. Hence GW waves being in the transverse traceless gauge. These two waves have a 45 degree phase shift from each other. This corresponds to the H positive and cross polarizations in image above. Also the quadrupole moment. spin 2 characteristic

Besides, I had exactly the same results as in the link. What is the point of your question? for those who can't watch the video: youtube.com/watch?v=eWbOXAEZyQA&t=615s

What Franken did was wrong. I didn't say otherwise. This is similar to what we saw all through the 2016 Election cycle; Clinton's email use was wrong and somehow that made her wrongs and Trump's wrong a wash. I think it is important not to do that. What Weinstein did is multitudes worse than what Franken did. Being able to identify that shouldn't be an apoligist position.

What Franken did was wrong. He admitted it and isn't making any excuses. I think it is important not to apathetically treat every situation of a famous person being outed for bad behavior as equal. Unlike others (Weinstein, Moore, C.K., Stallone, Trump, etc) Franken isn't being accused of Rape, molestation, public masterbation, or etc. What Franken did was a misdemeanor at most and not felon behavior. Neither the picture or the kiss would send someone to prison. The behavior is bad and women are too often objectified in society but we shouldn't lower the bar at the top end for those perpetrating heinous criminal acts by pretend all bad acts however large or small are the same.

But that wasn’t caused by black holes. https://www.forbes.com/sites/startswithabang/2017/06/08/newest-ligo-signal-raises-a-huge-question-do-merging-black-holes-emit-light/

Sadly those willing to be honest will be honest will be vilified while those without either honesty of regret with cling to plausible deniability. We must not overly persecute the truthful in order to make up for the shameless and dishonest.

Perhaps a hand wringing gotcha fail, like the Uranium One outrage nonsense. Then proceeded to list the victims from twenty plus years ago and completely unrelated incident, so don't preach to me about staying on topic, when you clearly divert from it at your whimsy to avoid answering pointed questions. What Franken did is dwarfed by the accusations leveled at your president and a sexually deviant republican judge who preys on teenage impressionables. In fact, in your reply seems to relish the fact she was inappropriately treated ( as weak as it is) as a desperate attempt to draw a false equivalency to the real story in the news cycles lately. Epic fail.

Dark Energy also has absolutely no bearing on the original question. It is currently believed that the very first galaxies formed just prior to reionization some 400,000 years after the Big Bang. It is suggested that the active galactic nuclei (a.k.a. quasars/blazars) from what is widely believed to be elliptical galaxies that caused this reionization. However, it has also been suggested that the shape of a galaxy is determined by its rotation, and that is where Dark Matter does play a role. Elliptical galaxies having a relatively slow or no rotation, while the spiral types have a much greater rate of rotation. In such a case, the age of the galaxy would not necessarily determine whether it is elliptical or spiral, but rather the rate of its rotation. Thus, it could be possible for spiral galaxies to exist at redshifts z > 6. Sources: Early Reionization by the First Galaxies - Monthly Notices of the Royal Astronomical Society, Volume 344, Issue 1, 1 September 2003 Early star-forming galaxies and the reionization of the Universe - Nature 468, 49-55, November 2010 (free preprint)

My claim actually comes from the paper that originally created the Type Iax supernova category in March 2013. Source: Type Iax Supernovae: A New Class of Stellar Explosion - The Astronomical Journal, Volume 767, Number 1, March 25, 2013 If between 18% and 48% of all the Type Ia SNe prior to March 2013 should have been classified as the much dimmer Type Iax SNe, then the age of the universe, the acceleration of the universe, and the existence of Dark Energy need to be re-examined. However, it has absolutely nothing to do with Dark Matter. Dark matter exists independently from supernovae data. Nor are supernovae used to determine the existence of Dark Matter. We are able to directly observe the gravitational effects Dark Matter has on galaxies and light. However, we cannot say the same thing about Dark Energy. Dark Energy only exists because of the questionable supernovae data collected during the 1990s.

I can see it having an effect on the established age of the universe, and universal expansion/acceleration, depending on the preponderance of these types of supernovae at different stages of galactic formation/age of the universe. This would then have an effect on the need/quantity of dark energy required. But I don't see how it would affect the need for dark matter.

I'd prefer to review the current studies before replying on this topic. I have some resources available via colleague's etc. However I will state we never place too much faith in any cosmic distance measure methodology. Every method of the cosmic distance ladder has its range of applicable use and accuracy. This includes redshift, parallax, Stellar parallax, mass/luminosity, Tully Fisher. This also includes standard candles, there have been well published boundaries as to some of the inherent properties as long as I can remember. So a review of current findings I will need to familarize with.

In a sense Strange has a valid point. Early structure formation arises from regions where particles effectively drop out of thermal equilibrium. Dark matter is strongly supported as being one of the earliest matter particles to do so. However as we know so little about DM we can only estimate when this will occur. Unfortunately we cannot lab test the properties of DM to even estimate its total mass to apply a calculation as to when it will drop out of thermal equilibrium. IF DM drops out of equilibrium early enough then structure formation can occur far earlier, the rates can then be estimated via Jeans Instability and Density wave theory as to the time for Spiral galaxy formation, however there is two major problems. Lack of mass value for DM and the Dark ages beyond the surface of last scattering, using light we can only see so deep into the CMB opacity regions where baryonic matter starts to decouple and form atoms. Evidence supports DM as the original anistropy seeds and not baryonic matter. (baryonic matter decouples far too late)

The biggest issue does seem to be distance determination ( and has been constantly revised for the last century ). It would be nice if a new 'standard candle' or metric for distance determination also did away with accelerated expansion and dark energy. It would simplify cosmology ( slightly ).

I don't follow. Many of the people in this country who vote against the truth are poor.

+1 for the first honest perpetual motion claimer ever!

Negative 1, you are citing a conspiracy for which you have no evidence. More over the Senate, Republican (Trump's party) controlled Senate, voted 98-2 to sanction Russia for their actions against us during the 2016 Election. This isn't even a partisan issue. As for the transfer of power Republicans controlled the house and Senate during the Obama administration and currently control every branch.

funny that you should ask.

I think you are barking at the wrong tree. I have no problem admitting that my "experiment'" in no way respects the canons of scientificity. It was not made under controlled conditions and no measuring instruments were used. I t is more akin to casual observations than anything else. The results I obtained in this non-scientific way resemble very much those obtained by Bragg in his short film. I was able to walk around the water tank, and no, I could not see the beam from above when it was not reflected by the (hand held) mirror. At least not from the same position as shown By Bragg. In this sense, there was no difference between what he showed and I saw. There was a difference though, and that is I think the reason why I was not entirely clear: even when the beam was not reflected on the mirror, and even when I could not see it from above from the same position, I could see it from the end of the path of the beam. That is from the position opposite to where the lamp was. My impression was that the beam did not go as far as when it was visible from above, but since I did not measure it, I will not claim that is the case. I will therefore stick to Bragg's observation that the beam either was reflected on the mirror without being visible from the side, or vice versa. That is also all I have assumed in all this discussion. So, if you want to be pedantic and accuse me of presenting a non-scientific experiment, then I will gladly plead guilty. Now stop beating about the bush and say what you have to say.

nope. I have nothing more to say. edit: gee! How strange! I wonder who voted me down?

@J.C.MacSwell, you should understand one thing - logic first. The logic says that in this case a non-simultaneously moving doors cannot touch each other. That's a very simple logic. Don't try to find the touch point somewhere else. There is no such point for the non-simultaneously moving doors in the ladder FoR. If you argue this, no offense but I'll have to ignore your arguments. @studiot, whether you insert "apparent" for a paradox, or you think of it as a real paradox, does not change the fact, that its existence question the validity of a statement. However, we are not discussing the ladder paradox here, but just using it as a base for discussing the relativity of simultaneity. You can safely ignore the question whether the ladder passes the garage or not. Our focus is on the event which I introduced in the experiment. @Janus, I'm sorry, but your notes on the drawings and your sketches don't make any sense to me. I think that you are confused with my drawings. The doors stop when they meet at the red dot, and that event of meeting (touching) each other is what you should focus on. If you don't find that event in the ladder FoR, then there is something wrong with relativity of simultaneity. Good luck guys.

Ten Oz, If you have not noticed, there is a deep state operating in the U.S. where political power is wielded inappropriately by federal employees even after the power has officially switched into other hands. The peaceful transition of power is a hallmark of our democracy. Yet the people elected to govern us, are acting like the current president is illegitimate and are marking time, until his removal from power. This is bu(*cr(*. He is our president. Senators should govern and make the laws that will serve us all. I agree with Trump, that the weather changes and the Earth goes in cycles. Small things that we do, can cause self reinforcing moves, like it gets a little warmer, some ice melts, and less sunlight is reflected back into space and more is absorbed. So yes, we did it to the planet, but we all did it. It is not a political issue, it is the current state of the planet. Regards, TAR

No, you just make it too simple. If I remember correctly you are one of the people who think that we see an object because its reflection, the rays emanating from it, enter our eyes. And still we see all those parallel rays.

Yes it does. But it's not surprising that you think that. A gravitational force field exist out of quanta. When light interacts with a force field, the photons scatter....this is gravitational scattering. The graviton is an elementary particle that mediates the force of gravitation in the framework of quantum field theory. The existence of a graviton is I think not (sufficiently) proven. But that doesn't matter, refraction (this is not gravitational lensing) reflection, diffraction, doppler effect...are abouut observable wave behavior and have its origins in scatteering. I don't understand why you people can't understand this.

Strange, Yes I think it unfair to ask rich people to pay more taxes, now after graduated income tax is already established, and all the arguments for having graduated income tax already are spent. You can not ask for more from the rich every time you need more money to spend. It is a denial of some basic facts of existence. Most people work for someone or some company that provides a good or service to people. The people and companies that do this the best get the most business. It is not luck. If you make your company or your employer pay more taxes, that is less money potentially to put in your paycheck. Or if you have a 401 K and this money is invested in companies, then the more taxes the companies you own through your 401K pay, the less money they can pay your account in dividends. Rich people are not our enemies, they are the holders of the means of production. And again, what does it matter whether dire predictions raise the levels of the oceans 2 feet or 8 feet by 2000. What matters is whether we come up with the strategies to sequester carbon and find renewable sources of energy and adjust our life styles to take better care of our resource. Not forced to do it, but to do it, because its better to do it than not. It would be better for the planet if we did not fly and drive around or live in climates where we need heating or cooling. We actually don't have many places to live where we do not have to protect ourselves from the elements, so we are destined to stress the place. It is not realistic to ask people to stop living, to save the planet for someone else. Regards, TAR Ten Oz, Neg 1 to you, for no particular reason. And I will use your vote as a reason to take another restbit from political discussions. I hate neg reps, and don't deserve them. Regards, TAR